This application claims benefit of Japanese Application No. 2000-99326 filed in Japan on Mar. 31, 2000, the content of which is incorporated in this reference.
1. Field of the Invention
The present invention relates to an electric bending endoscope device, which is provided with an endoscope wherein a bending portion is bent by electrical driving means.
2. Description of the Related Art
Conventionally, a long, thin endoscope is inserted into jet engines or pipes in power plants and observations and various procedures are performed. Typically, a soft insert portion, formed in the endoscope, is provided with a bending portion. This endoscope is provided with a bending apparatus f or bending the bending portion by moving a pulling element such as a bending wire which is passed through the bending portion.
By using this bending apparatus, insertion into a subject area, for example, can be performed easily, while the optical monitoring system disposed on the end of the endoscope insert portion is oriented towards the object.
Recent endoscopes use electric motors to power the bending apparatus. In effect, the bending portion is bent by moving the bending wire with the driving power of the electric motor. By bending the bending portion with an electric motor, the bending operation is significantly improved compared to conventional manual systems. The electric motor of the bending apparatus is powered by an external power source such as a battery or an AC power source.
However, for a bending apparatus using a power source such as the above-mentioned battery, the bending portion will become fixed in the bent position if the battery fails or if the battery voltage drops when the bending portion is being bent. On the other hand, for a bending apparatus using an AC power source as the power source, the operation of the entire apparatus will halt and the bending portion will become fixed in the bent position in the event of a power failure.
For this reason, in order to withdraw the insert portion when there are problems with the power supply, it is necessary to wait until the power is recovered, and then to release the bent state and withdraw the device, when the power source is an AC power source. On the other hand, when the power source is a battery or the like, it is necessary to recharge the battery or replace the battery, and then release the bent state and withdraw the device.
On the other hand, when withdrawing the insert portion from the pipe or the like while the bent state is maintained, a corresponding amount of time is required to withdraw the insert portion because the bending portion is in a bent state. Even when the bent insert portion is withdrawn, for example, the tip of the insert portion that is in the bent state becomes problematic, when storing this insert portion in a storage case, and it becomes impossible to store the device properly.
It is an object of the present invention to provide an electric bending endoscope device that will facilitate the withdrawal of the insert portion, even when the bending operation of the bending portion cannot be performed because of a problem with the power source, such as a battery failure or power failure, when the bending portion is in the bent state.
Basically, the electric bending endoscope device according to the present invention comprises: an endoscope having a bending portion; a bending control mechanism which electrically drives the bending portion of the endoscope; a source voltage monitoring portion for monitoring the source voltage supplied to this bending control mechanism; and a change-over switch for releasing the bent state of this bending portion, when the above-mentioned bending portion is in the bent state, based on the output signal from this source voltage monitoring portion; wherein it is possible to release the bent state of the bending portion and withdraw the insert portion, even when it becomes impossible to perform the bending operation due to a battery failure or the like, while the bending portion is in the bent state.